1. Field of the Invention
The present invention relates to a thermoplastic resin composition which is excellent in mechanical properties, heat resistance and moldability, and a molded article thereof.
2. Description of the Related Art
For the purpose of improving the chemical resistance of an aromatic polycarbonate resin, and improving the impact resistance and the flowability during the mold processing of an aromatic polysulfone resin, various thermoplastic resin compositions comprising an aromatic polycarbonate resin and an aromatic polysulfone resin are disclosed.
For example, JP-B-45-39181 discloses that chemical resistance and thermal stress brittleness are improved compared with each resin by mixing an aromatic polysulfone resin and an aromatic polycarbonate resin.
JP-B-49-13855 discloses that a composition comprising an aromatic polysulfone resin and an aromatic polycarbonate resin is excellent in heat-deformation resistance compared with ABS resin.
JP-A-54-28361 discloses that a composition comprising an aromatic polycarbonate resin having a weight average molecular weight of larger than 60000 and an aromatic polysulfone resin, has a improved chemical resistance and good temperature of deflection under load compared with the respective resins.
Moreover, JP-A-60-51739 discloses that a composition comprising an aromatic polysulfone resin and an aromatic polycarbonate resin containing specific structures is excellent in a mechanical property, and improved in chemical resistance.
However, the above described compositions can not satisfy the physical properties in many cases, since an aromatic polycarbonate resin lowers the excellent physical properties, such as the heat resistance which is inherent in an aromatic polysulfone resin.
JP-A-60-5108 discloses a microwave oven container comprising an aromatic polysulfone resin. However, a container comprising an aromatic polysulfone resin alone has sometimes insufficient flowability during mold processing, and it is hard to obtain a molded article having a good appearance.
For a lamp reflector (referred to as "a reflecting mirror", sometimes), especially for a head lamp reflector and a fog lamp reflector of cars, a metallic material such as a sheet steel or a glass material has been conventionally used.
In recent years, various designs are demanded and a resin material having an excellent processing property and a high degree of freedom has been demanded. Under such a background, a bulk molding compound (BMC) in which an unsaturated polyester resin is reinforced with inorganic fillers, such as a glass fiber, came to be used as a material for the above use.
Further, as a lamp reflector material, a polycarbonate and a polyphenylene sulfide resin which are thermoplastic engineering plastics, have been examined for the purpose of improving a recycle property of the materials, performance, and a mold processing property. However, in the use of a halogen lamp with a high temperature of light source, or in the use of a projector type reflector from which a large quantity of light can be obtained, there may be a problem that the heat resistance is insufficient to generate heat deformations. In order to raise the forward visibility of a vehicle, a reflection property on the surface of a reflector is important, and the surface needs to be smooth. Therefore, an undercoat processing is made on the surface of a molded material and it is industrially disadvantageous.